Speedometer drive for motor cycles



June 3, 1930: M E. JONES 1,761,833

SPEEDOMETER DRIVE FOR MOTOR CYCLES Filed Oct 27. 1924 IN V EN TOR. M10 wy/vfljwis, v

A TTORNE Y.

Patented June 3, 193 0 I Th s - ATE T FF I MALVDWYN EVANS JONES, or INDIANAEV'OLIS', INDIANA ,lsrnnnorlrnrnemrtrvn FOB, Moron, CYCLES A plication filed October 27,1924. Serial N6. 746,013. 7

It isthe object of my invention tosimplify and cheapen certainpdriving'mechanism es pecially for a motorcycle speedometer.

It is usual in driving the speedometer of, I a motorcycle to mount a special gear'on one of the motorcycle Wheels, usuallyv the rear wheel, with which special gear'meshes a pinion which is connected tothe fiexlble shaft, leading to the speedometer. This is both expensive and troublesome. It involves mounting the main speedometer-driving gear on thezspokes of the rear Wheel, so that the gear getsout of true if any of the spokes stretchor break. In additiomit is unsightly, especially as' this main gear is ordinarily bigger than the brake drum.

By my invention, I do away entirely with this extra gear. Instead of driving the speedometer-driving pinion from such a zo special gear, I drive it from the sprocket which forms part of the chain-drive for the driving wheel of the motorcycle. That is,

the pinion on the end of the flexible shaft pleading tothe speedometer is mounted to mesh as a gear with the sprocket of the chaindrive for the rear wheel of the motorcycle, desirably with the sprocket on' the 7 rear wheel itself. Thus such sprocket serves both as a sprocket in the chain drive'for the wheelgand as. a gear-in the gear drive for the speedometer.

The accompanying drawing illustrates my invention: Fig. 1 is a side elevation of a motorcycle having a speedometer drive equipped with my invention, the driving mechanism for the rear wheel and the speed- 7 ometer being shown in full lines, and the motorcycle as'a whole being shown in broken lines; and Fig. 2 is an enlarged fragmental View showing the sprocket cooperating both with the chain which drives it and the pinion which it drives,

The motorcycle has the usual frame 10,

,front wheel-ll, and rear wheel 12, with the usualsprocket 13 on the rear wheel 10 for 7 driving it. As is usual, this sprocket 13 is connected by a chain late a suitable sprocket"l5ldriven bythe usual engineflG. The

' I L. parts. 10 to 16 inclusive mayiconforn to any 'i ordinary' construction.

' The chain 14; meshes with'a fractionone-half,jmor'e or less of the circumference of'ea'ch sprocket l3 andl5 butbetween the 't wo stretches'of the chainl there are a number of teeth of each sprocket which are out of mesh with the chain. I make use'of these chain-free teeth to drive the speedometerQO, which is mounted on the frame 10 in any usual and convenient location. To this end, I provide'a pinion 21 which l'IlGSil- -es with one of the'sprockets of the chain is not a theoretically correct gear-tooth structure, I have found inactual practice that it is entirely'eifective and sufiicient' for driving the pinion 21 from the sprocket 18. "The pinion is mounted in any suitable supporting structure 22carr1ed by the frame 31 10,w'hich supporting structure may be of any ordinary construction. The pinion 21 is suitably connected to the rear lowerend' of a fiexibleshaft 23, which leads forward and upwardfto the speedometer 20 to drive such speedometer.

IVhile by way of example Ihavedes'cribed my invention in connection witl'i thefspeedometer drive'ofa motorcycle, "in which use it is especially desirable, itis'not limited to 0 that "specific drive but is broadly applicable to all that is includedwithin the scope of thefappended claims. w

I claim as my invention 1. In combination with a motorcycle fram'e having re'arwardly convergent upper and lo'wer framebars providing a space; there-between, a road wl1eei. o'urnaled in the riemea h m sprocket carried by said road wheel and havingteethseparated by rounded lUU roller cavities, a driving chain extending iroin the lower portlon of the sprocket, about the rear and over the top of the same and'leaving the front portion'of the spocket bare and exposed to the unoccupied space between the convergentfranie'bars a bracket 7 mounted on one of thesaid fraine barspart said 'sproketfbnt'clear of the, remainder of ly in the space between thetwo apinienhaving f rounded substantially cylindrical faced teeth to fit the roller cavities in" the chain p o saidwrc ind: to th sprock t being supported by said bracket 'i'nthe space between the frame bar-s inmesh" with the unused teeth of the chain sprocket atthe forward uncovered side of thesaineiand- I thereby directly driven by said chain driven)".

'--In,witn sawh eofi.Ii ha e a drivendevice mounted on said motorcycl st means for driving said driven devlce from said sprocketgjsaidf la$ fl amedfnreansl iIl-II'I eluding pinion having teeth;-shaped to?f. V i j] meshwith the chain-engaging teeth of said sprocket; and means for rotatably supporting said pinion in inesh with said sprocket Y Q at a point on thesproc'k'et: circumference where thes'prooket teeth'ar'efree from eni gagement"with said chain.

"myhand at Indianapolis, lndianaflhis l'ith day of 'fictobeig} D; one thousand nine.

hundred and twenty four;

sprocket and aspeedometer or like drive s'haftactuated by, said round tooth, Pinion, I

' 2-. I 1. combination \iviih aJIiOtOrQycle h'avchain sprocket on: ne .jwtheelj and q drive. ch in. i nding' o t acportion of thesmfie, aid un sed portion, of "the. chain sprocketbeingnexposedto a clarispacebetween the opposite runs, of the drive, chain,-

a} pinion having teeth spaced in accordance with; the spacing of the chain sprocket teeth bare unusual-teeth of; the chain sprocket and:

V a speedometer, or like drive shaft supported y said bracketanddrtyen by "saidiprovcketn i driven Pinion." 7

:3. In combination, a. chain-sprocket having; an ann la-r series oi chain-engaging teeth, a engaging saidseries offteeth for only; a portion oiithe circumference of V the sprocket, pinion having an annular c series-of teeth' shaped; to mesh with; the chain-engaging; teeth of said sprocket, and; i means for rotatably lsnpportiiig saifl' liinion' in". association with said sprocket with" the pinion teeth engaging the; sprocket test-hat; v V a point-on the sprocket-cireumterencefwhere the sprocket teeth are free from engagement withsaid chain. t H a n T4,; lnicornbination' with a chaiii drive hai I i ing-two toothed sprockets and a. chaininften; connecting -them,l'a,jpijnion haying teeth shapedflto mesh-with thech engaging;

teeth. of 0m; Deena pregkets; and means for" mummy; fS PPQi g said pin mesh -.-with one of'saidsprocketsfat ei ointjibea tween the two stretc-hesjof to the other sprocket;

c meter e- 5. a; motorycle, a" driving iiwheeh' a;

toothed chain; ,Spleka rotatable with Said driizing wheel, meansiori driving saidwheel;

saidl'meansfincluding a chain Qeng'aging said sprocket fora portion its cirerunference,

' MALDWYN EVAN N S- i it hereunto set i 7 so a 

